The 8051 Microcontroller and Embedded

Department of Computer Scien

ce and Information Engineering

National Cheng Kung University
HANEL
SERIAL COMMUNICA-TION
PROGRAMMINGDoubling Baud

Rate(cont’)

4800

2400

F4

-12

SMOD=1 192009600 2400

1200

E8

-24

4800

FA

-6

9600

FD

-3

SMOD=0

(Hex)

(Decimal)

TH1

XTAL oscillator Baud Rate comparison for SMOD=0 and SMOD=1

÷^12

÷^16

SMOD = 1

Machine cycle freq921.6 kHz

28800 Hz

To timer 1 To set the Baud rate

÷^32

57600 Hz

11.0592 MHz

SMOD = 0